Versus

Ouai Hydrating Scalp Serum for Healthy, Fuller Looking Hair Versus Kérastase Genesis Strengthening Serum for Hair and Scalp

Hair Serum
Hair Serum
American Brand United States
French Brand France

Overview

What they are

These products are both reef safe hair serums. They have a total of 6 ingredients in common

Cool Features

They both contain Vitamin E

Suited For

They're both likely to be good for anti aging, dry skin, brightening skin, reducing pores and scar healing

Free From

They both do not contain any parabens, silicones or sulfates

What's Inside

They both contain common allergens and fragrances

We independently verify ingredients, and our claims are backed by peer-reviewed research. Spot a product that needs an update? Let us know.

Ingredient Info

Click any item below to learn more and see relevant ingredients

About this product

About this product

At a glance

Click on any of the items below to learn more

Key Ingredients

Benefits

Concerns

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

found in both products
Hydrating Scalp Serum for Healthy, Fuller Looking Hair

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Skin Conditioning, Solvent

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Stay hydrated!

Learn more about Water
Antioxidant, Masking, Skin Conditioning

Tocopherol (also known as Vitamin E) is a common antioxidant used to help protect the skin from free-radicals and strengthen the skin barrier. It's also fat soluble - this means our skin is great at absorbing it.

Vitamin E also helps keep your natural skin lipids healthy. Your lipid skin barrier naturally consists of lipids, ceramides, and fatty acids. Vitamin E offers extra protection for your skin’s lipid barrier, keeping your skin healthy and nourished.

Another benefit is a bit of UV protection. Vitamin E helps reduce the damage caused by UVB rays. (It should not replace your sunscreen). Combining it with Vitamin C can decrease sunburned cells and hyperpigmentation after UV exposure.

You might have noticed Vitamin E + C often paired together. This is because it is great at stabilizing Vitamin C. Using the two together helps increase the effectiveness of both ingredients.

There are often claims that Vitamin E can reduce/prevent scarring, but these claims haven't been confirmed by scientific research.

Learn more about Tocopherol
Buffering, Masking

Citric Acid is an AHA derived from citrus fruits (think oranges, lemons, and limes!).

As an AHA, Citric Acid removes the top layer of skin cells from the newer layer of skin underneath. This helps skin to remove dark spots and even out skin tone.

If you spot Citric Acid near the end of an ingredient list, it's likely there as a pH adjuster rather than an active ingredient.

Read more about some other popular AHA's here:

Learn more about Citric Acid
Masking, Perfuming

Parfum is a catch-all term for an ingredient or more that is used to give a scent to products.

Also called "fragrance", this ingredient can be a blend of hundreds of chemicals or plant oils. This means every product with "fragrance" or "parfum" in the ingredients list is a different mixture.

For instance, Habanolide is a proprietary trade name for a specific aroma chemical. When used as a fragrance ingredient in cosmetics, most aroma chemicals fall under the broad labeling category of “FRAGRANCE” or “PARFUM” according to EU and US regulations.

The term 'parfum' or 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.

For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance by INCI standards.

One example is Calendula flower extract. Calendula is an essential oil that still imparts a scent or 'fragrance'.

Depending on the blend, the ingredients in the mixture can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.

Parfum can also be used to mask or cover an unpleasant scent.

The bottom line is: not all fragrances/parfum/ingredients are created equally. If you are worried about fragrances, we recommend taking a closer look at an ingredient. And of course, we always recommend speaking with a professional.

Learn more about Parfum
Perfuming, Solvent

Limonene is a fragrance that adds scent and taste to a formulation.

It's found in the peel oil of citrus fruits and other plants such as lavender and eucalyptus. The scent of limonene is generally described as "sweet citrus".

Limonene acts as an antioxidant, meaning it helps neutralize free radicals.

When exposed to air, oxidized limonene may sensitize the skin. Because of this, limonene is often avoided by people with sensitive skin.

The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term. For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance.

Learn more about Limonene
Perfuming

Linalool is a fragrance and helps add scent to products. It's derived from common plants such as cinnamon, mint, citrus, and lavender.

Like Limonene, this ingredient oxidizes when exposed to air. Oxidized linalool can cause allergies and skin sensitivity.

This ingredient has a scent that is floral, spicy tropical, and citrus-like.

Learn more about Linalool

When to use

12 Routines
42% use in am
58% use in pm
92% use every day
3 Routines
67% use in am
33% use in pm
100% use every day

Reviews

Here's what our community thinks

Ouai Hydrating Scalp Serum for Healthy, Fuller Looking Hair 28 ingredients

Hydrating Scalp Serum for Healthy, Fuller Looking Hair hasn't been rated yet.
Rate it now

Kérastase Genesis Strengthening Serum for Hair and Scalp 29 ingredients

3.0 /5
from 1 rating
justphil's avatar

Philip

8 months ago
Review

This only works if you’re consistent. I only saw a difference when I applied this day and night. They released a different formula for males. So, maybe that formula would work better on me.